TM 9-585 Range Finder M9, 1943-10-19
"Disassembly, assembly, and such repairs of the materiel as may be handled by the using arm personnel are described in this manual. They will be undertaken only by the battery mechanic."
Digitized by the Combined Arms Research Library Digital Library, US Army Combined Arms Center http://cgsc.cdmhost.com/cdm/
"19 October 1943."
"The range finder is an optical instrument used for measuring the distance of a target or other object."--Introduction
Includes bibliographical references (page 38) and index